Hallucigenia Sparsa: Worm-Like Creature With Legs And Spikes On Its Back Found b4in.org/h7GB One of the most bizarre-looking fossils ever found – a worm-like creature with legs, spikes and a head difficult to distinguish from its tail – has found its place in the evolutionary Tree of Life, definitively linking it with a group of modern animals for the first time. Image: This is a reconstruction of the Burgess Shale animal Hallucigenia sparsa. Credit: Elyssa Rider The animal, known as Hallucigenia due to its otherworldly appearance, had been considered an ‘evolutionary misfit’ as it was not clear how it related to modern animal groups. Researchers from the University of Cambridge have discovered an important link with modern velvet worms, also known as onychophorans, a relatively small group of worm-like animals that live in tropical forests. The results are published in the advance online edition of the journal Nature. The affinity of Hallucigenia and other contemporary ‘legged worms’, collectively known as lobopodians, has been very controversial, as a lack of clear characteristics linking them to each other or to modern animals has made it difficult to determine their evolutionary home. What is more, early interpretations of Hallucigenia, which was first identified in the 1970s, placed it both backwards and upside-down. The spines along the creature’s back were originally thought to be legs, its legs were thought to be tentacles along its back, and its head was mistaken for its tail. Hallucigenia lived approximately 505 million years ago during the Cambrian Explosion, a period of rapid evolution when most major animal groups first appear in the fossil record. These particular fossils come from the Burgess Shale in Canada’s Rocky Mountains, one of the richest Cambrian fossil deposits in the world. More b4in.org/h7GB
Posted on: Sun, 17 Aug 2014 20:40:24 +0000
Trending Topics
Recently Viewed Topics
© 2015